Mercedes von Martritz, the gentle soul from the Blue Lions House in Fire Emblem: Three Houses, begins her journey with a D rank in Faith, positioning her as the designated healer for this house. However, players quickly notice that her starting Faith proficiency is actually lower than both Linhardt and Marianne, who both start at D+. This initial disparity impacts her early game healing capabilities, particularly in the challenging Maddening difficulty.
For Blue Lions players, Mercedes’ slightly slower start in Faith means that accessing the invaluable Physic spell takes a bit longer. While it’s achievable by Chapter 3 even without relying on lecture boosts, prioritizing Faith in her goals is crucial to maximize her growth rate (1.5x) and potentially dedicate lectures to other units. On Maddening difficulty, which discourages New Game+ advantages, players are limited to just 5 uses of basic healing spells during Chapter 2, a notoriously lengthy chapter. This often necessitates equipping every unit with Vulneraries to sustain them through battles. In contrast, Linhardt and Marianne can realistically obtain Physic by Chapter 2, granting them 8 healing spell uses, significantly easing early game pressure compared to Mercedes’ initial 5.
Even when Mercedes acquires Physic in Chapter 3, she starts with only 3 uses, less than the 5 uses mission assistance Linhardt and Marianne offer due to their higher starting level (Level 5). They also boast a greater range for Physic at this stage. This can lead some players to consider replacing Mercedes with these readily available healers once out-of-house recruitment becomes possible and Intermediate classes unlock. While it’s feasible to level Mercedes by strategically feeding her kills, this comes at the cost of hindering the growth of your offensive units who might benefit more from combat experience.
However, Mercedes possesses a unique in-house synergy that sets her apart: her support with Annette. At A Support, they grant each other +3 Might. If you intend to utilize Annette in your team, leveraging Mercedes as an adjutant can be strategically advantageous, especially if you aim to unlock Pegasus Knight for Annette at level 10 and eventually guide her towards becoming a powerful Wyvern Lord wielding Bolt Axes. If a Wyvern Lord Annette isn’t your goal, the necessity of heavily investing in Mercedes diminishes.
Chapter 13 presents a particular challenge where Annette and Mercedes begin in precarious starting positions. Despite this, training Mercedes isn’t mandatory for survival. A clever strategy involves using Stride and Impregnable Wall gambits on a flying Byleth to bypass the danger. Reaching level 10 with Mercedes can be beneficial for her paralogue, enabling her to fly to safety if needed. However, if she remains grounded, and the map is cleared swiftly, she isn’t necessarily in significant danger. Recruiting Linhardt remains highly desirable, as he is one of the limited non-DLC Warp users in the game, offering invaluable tactical options despite the spell’s shorter range compared to Lysithea’s.
Venturing outside of the Blue Lions house, mission assistance Mercedes doesn’t gain Physic until Chapter 5. She becomes a more compelling recruitment option starting in Chapter 6, coinciding with the availability of Intermediate classes for recruited units. Delaying her recruitment until Chapter 7 might be beneficial for slightly improved base stats and a higher starting level. The extended range of her Physic as an out-of-house recruit proves particularly useful on expansive maps like Chapter 7. Furthermore, she can immediately class into Pegasus Knight upon recruitment for her paralogue, which is useful even if long-term deployment isn’t planned.
In the Golden Deer route, Mercedes offers a viable alternative to Marianne as a dedicated healer, freeing up Marianne to excel as a Dancer. Marianne’s Riding boon and favorable starting position in Hunting By Daybreak make her an excellent Dancer candidate for the Golden Deer. This strategic shift allows you to maximize both units’ potential, as it’s generally more effective to dance with your Dancer rather than using them for healing during combat.
Finally, in the Black Eagles house, although her shared paralogue with Caspar is unavailable post-timeskip in Crimson Flower, Mercedes becomes a highly sought-after recruit for her adjutant capabilities, specifically for Jeritza. Her Might boost provides valuable offensive support to Jeritza, a formidable unit who greatly benefits from increased damage output. Mercedes’ versatility and house-specific advantages make her a nuanced and strategically interesting unit to consider throughout your Fire Emblem: Three Houses playthroughs.
